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 * this work for additional information regarding copyright
 * ownership. Elasticsearch licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
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 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
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package org.elasticsearch.search.aggregations.metrics.weighted_avg;

import org.elasticsearch.search.DocValueFormat;
import org.elasticsearch.search.aggregations.Aggregator;
import org.elasticsearch.search.aggregations.AggregatorFactories;
import org.elasticsearch.search.aggregations.AggregatorFactory;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.search.aggregations.support.MultiValuesSource;
import org.elasticsearch.search.aggregations.support.MultiValuesSourceAggregatorFactory;
import org.elasticsearch.search.aggregations.support.ValuesSource.Numeric;
import org.elasticsearch.search.aggregations.support.ValuesSourceConfig;
import org.elasticsearch.search.internal.SearchContext;

import java.io.IOException;
import java.util.List;
import java.util.Map;

public class WeightedAvgAggregatorFactory extends MultiValuesSourceAggregatorFactory<Numeric, WeightedAvgAggregatorFactory> {

    public WeightedAvgAggregatorFactory(String name,  Map<String, ValuesSourceConfig<Numeric>> configs,
                                        DocValueFormat format, SearchContext context, AggregatorFactory<?> parent,
                                        AggregatorFactories.Builder subFactoriesBuilder,
                                        Map<String, Object> metaData) throws IOException {
        super(name, configs, format, context, parent, subFactoriesBuilder, metaData);
    }

    @Override
    protected Aggregator createUnmapped(Aggregator parent, List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData)
            throws IOException {
        return new WeightedAvgAggregator(name, null, format, context, parent, pipelineAggregators, metaData);
    }

    @Override
    protected Aggregator doCreateInternal(Map<String, ValuesSourceConfig<Numeric>> configs, DocValueFormat format,
                                          Aggregator parent, boolean collectsFromSingleBucket,
                                          List<PipelineAggregator> pipelineAggregators,
                                          Map<String, Object> metaData) throws IOException {
        MultiValuesSource.NumericMultiValuesSource numericMultiVS
            = new MultiValuesSource.NumericMultiValuesSource(configs, context.getQueryShardContext());
        if (numericMultiVS.areValuesSourcesEmpty()) {
            return createUnmapped(parent, pipelineAggregators, metaData);
        }
        return new WeightedAvgAggregator(name, numericMultiVS, format, context, parent, pipelineAggregators, metaData);
    }
}
